A washing machine uses power from an electric motor as main power, and performs washing, rinsing, and drying processes to remove dirt or stains on laundry through the action of detergent and water. The washing machine includes an electric motor, which is a power apparatus, a mechanical part that transfers energy from the motor to the laundry, a controlling part controlling the washing process, a water supply apparatus, and a water draining apparatus.
Washing machines may be classified into agitator type washing machines, pulsator type washing machines, and drum type washing machines, depending on their washing scheme. An agitator type washing machine performs washing by horizontally rotating a wing-shaped agitator in the center of the washing tub, and the pulsator type washing machine performs washing using waves generated by rotating a disk-shaped pulsator. A drum type washing machine includes a drum having a plurality of protrusions formed thereon. The drum type washing machine performs washing using impact generated when the laundry is lifted by a lifter in the drum and then dropped into the wash water and detergent in the drum as a result of rotating the drum around a horizontal axis.
The drum type washing machine performs washing of the laundry by dropping the laundry lifted up by a lifter. However, when the laundry is not lifted up sufficiently, the drum type washing machine suffers from a decreased washing efficiency. Moreover, it is not easy to lift the wash water using the lifter, which may result in less than ideal circulation of the wash water in the drum.
Therefore, there is a need to solve the problems.